Clamp for case carrying trucks



April 9, 1963 w, Q

CLAMP FOR CASE CARRYING TRUCKS Filed April 14, 1960 INVENTOR. WiLLIAM 6'MALO Wc'ZZlwnum-n, J

A 7' TOPNE KS United States Patent Ofitice 3,084,826 Patented Apr. 9,1963 3,084,820 CLAMP FOR CASE CARRYING TRUCKS William G. Mala, Marshall,Mind, assignor of one-half to Rolland Sherman, Marshall, Minn. FiledApr. 14, 1960, Ser. No. 22,338 7 Claims. (Cl. 214371) This inventionrelates to industrial hand trucks adapted for carrying cases of bottledgoods and frequently referred to as beverage case trucks.

An important object of my invention is an industrial hand truck which iscapable of picking up and transporting a stack of cases of bottled goodswithout requiring that the stack of cases be initially tipped to mountthe cases on the truck.

Another object is a new and improved case clamp or gripping meansadapted for use with a case carrying truck which is designed to grip acase of bottled goods at the usual apertures provided for the handholesto positively maintain and support a stack of cases of bottled goods ona hand truck during transportation thereof.

Another object is a case gripping and carrying clamp of the classdescribed which is substantially noiseless in operation and provides fora more positive clamping of the cases than has been heretofore possible.

Still another object is a case clamp of the class described which isadapted to engage cases of varying widths within reasonable tolerancesor limits to enable said clamp to work efficiently and permit a singletruck having the clamp of the instant invention mounted thereon to beemployed in carrying cases having a variance in span between thhandholes.

A further object is a case carrying truck having novel simply designed,easily mounted, relatively inexpensive case gripping and supportingmeans which are responsive to contact with the cases to be carried andautomatically enclose and support said cases when coming into contactwith same in a smoother, noiseless and more effortless fashion thanheretofore possible with prior art devices.

These and other objects and advantages of my invention will more fullyappear from the following description made in connection with theaccompanying drawings wherein like reference characters refer to thesame or similar parts throughout the several views, and in which:

FIG. 1 is a side elevation of a preferred embodiment of my inventionshown in cooperative relationship with a stack of cases of bottledgoods, the full line position showing the stack as it is initiallygrasped and the broken line position illustrating the position of thetruck and stack of articles during tilted transportation position;

FIG. 2 is a section taken approximately on the line 2--2 of FIG. 1;

FIG. 3 is a somewhat diagrammatic top plan view of the case gripping andsupporting clamp shown in FIGS. 1 and 2 illustrating the approximateextreme open and closed positions thereof with portions thereof brokenaway;

FIG. 4 is a somewhat diagrammatic top plan view of an alternate form ofmy invention showing the clamp in its approximate extreme closed andopen positions; and

FIG. 5 is a partial rear elevational view of the alternate form ofinvention illustrated in FIG. 4.

Reference is now made to the accompanying drawings for a more detaileddescription of my invention. The main body portion T of the truck bodyupon which my case gripping and supporting assembly or clamp is mountedmay be of any suitable design. A preferred type of truck body isillustrated in the accompanying drawings and consists of a generallyinverted U-shaped frame of rigid tubular construction and includes thevertical side members 10 which are interconnected by a series ofvertically spaced slightly rearwardly bowed cross bracing members 11,with a rearwardly extending handle member 12 provided at the top of theU-shaped frame. A pair of rearwardly extending bowed or arcuate shapedskid members or stair climbers 13 are connected as by welding to each ofthe side members 10 to enable the truck to be conveniently slid up anddown stairways and the like.

The stair climbers 13 have secured thereto as by welding a transverselydisposed foot piece 14 which also serves as the axle for mounting therubber tired wheels 15 thereon.

The case gripping and supporting assembly or clamp constituting theinstant invention includes a pair of similar case gripping jaws, arms orclamping members 16, 'which arms include the forwardly extending sideportions 16a adapted to enclose the sides of the cases 17, the backportions 16b disposed at approximately right angles to the side portions16a and adapted to be disposed opposite and enclose the backs of thecases 17 to be transported, and

the rearwardly extending offset end portions 160 upon which the armtensioning and actuating means are adapted to be mounted. These offsetend portions 160 are preferably slightly bent back upon the backportions 16b at an angle on the order of 5% or inclined slightly towardsthe sides and disposed at an angle somewhat less than degrees withrespect to the back portions 16b, preferably at an angle on the order of85 degrees with respect thereto for a purpose hereinafter to bedescribed.

The arms 16 are pivotally mounted on the truck frame by means ofbushings or collars 18 which are mounted on the side members 10 near thelower extremities thereof and somewhat above the extreme lower end orfoot thereof and above the lower join between the stair climbers '13 andthe side members 10. This enables the arms 16 to be disposed atapproximately the same height as the hand hold apertures 19 of the cases17 and in substantial alignment therewith.

The outer or leading ends of the side portions 16a are provided withinwardly projecting lateral extensions or ears 20 which are adapted tobe inserted into the hand hold apertures 19 of the cases 17 topositively support and lift the cases.

Novel elongate, elastic or resilient tensioned clamp arm teusioning andactuating means are provided in the form of a strong helically coiledspring 21 in FIGS. 1-3 inclusive which spring extends between andengages these rear offset portions 16c and is secured thereto by anysuitable means such as the nutted bolts 22. Cylindrical guide or insertmembers 23 are inserted axially into the outer ends of the spring 21 andsurrounded by several convolutions thereof to provide for more positiveactuating engagement between the spring 21 and the arms or jaws 16. Thespring is axially compressed to suitably tension same and cause it tonaturally assume a bowed or flexed position and continuously bear orpush against the offset portions to which it is attached and bias orhold the arms 16 in one direction or the other (towards open or closedposition) depending on the relative position of the spring with respectthereto, the medial portion of the spring being capable of and adaptedto flexing or yeilding to assume the bowed positions shown in theaccompanying drawings as dictated by the relative positions of the clamparms 16 with respect to each other, the medial portion of the springtending to follow the course of least resistance when subjected to axialcompression or compressive forces and buckling in one direction or theother, depending on whether the clamp arms 16 are open or closed andholding said arms in one of said positions.

The spring 21 provides what might be termed an overcenter action formoving and maintaining the arms inwardly or outwardly depending on whichside of the center line cl the spring is disposed. The center linereferred to is the line extending between and bi-secting the points ofpivotal connection of the arms with the truck frame or the axes ofpivotal movement of said arms. It will be noted that the center portionof the helical spring 21 is free to move laterally in any direction, andit will be readily appreciated by those skilled in the art that acompressively tensioned helical spring tends to bow outwardly at thecenter portion or point of least resistance thereof to relieve thecompressive tension thereon. Therefore, when the spring 21 is disposedforwardly of the line cl bi-secting the collars 18 (as shown by thebroken line position of FIG. 3), the clamping and supporting arms is areheld outwardly and positively maintained in that position until thespring is moved rearwardly past the center line (as shown by the solidline position of FIG. 3) at which time the spring bows towards the rearand pulls the arms inwardly into clamping, supporting position. Thus,the helical spring 21 provides for positive clamping action and alsoprovides a positive means for maintaining the arms in an outwardlydisposed inoperative position. In addition to the positive clampcontrolling action provided by the spring, the spring also has otherimportant advantages in that it provides for very smooth substantiallynoiseless operation with no banging or clanging of metal parts takingplace.

In use and operation, the truck with the arms or jaws 16 of the carryingclamp in the outwardly extended broken line position of FIG. 3 is movedagainst a stack of cases 17 which movement may be assisted by theoperator pushing against the foot piece 14-. As the back portions 16b ofthe arms J16 engage the back of the lowermost case, they are pressedrearwardly causing the side arm portions 16a to move towards the sidesof the case and cause the engagement and supporting ears 2% to beinserted into the hand hold apertures 19 of the cases as best seen inFIG. 2. As the spring 21 reaches the center iine cl between the pointsof pivotal connection, it re- Verses position and moves or bowsrearwardly, and at the same time applies positive pressure against theoffset end portions 160 and continuously urges them apart, therebypositively holding the side portions 16a against the sides of the caseand maintaining the supporting ears 20 in the hand hold apertures 19 andinsuring that they will remain there. The offset end portions 16c may bemaintained or disposed at right angles to the back portion 16b tomaintain the spring 21 in substantially straight alignment. However, aspreviously described, I have found that a more positive clamping orretaining action is provided if the end portions 16c are slightlyangularly offset from the back portion 1612 by approximately degreeswhich causes the spring in clamping position to bow rearwardly as bestseen in FIG. l2, thereby eifecting a more positive locking and clampingaction than would otherwise be provided and eliminating any possibilityof the arms becoming inadvertently disengaged from the cases prior tothe lifting and transporting thereof.

Bottle carrying cases vary somewhat in size depending on themanufacturer thereof and to allow for this variance in size, thecarrying clamp or case gripping assembly of my invention is adapted tomaintain a positive gripping action for engaging and supporting thesmaller cases in which the side arms 16:: are disposed somewhat inwardlyand converge slightly towards one another and tending to assume thesolid line position of FIG. 3. However, due to the positive action orthrust applied by the rearwardly bowed spring 21 in such a circumstance,the arms and the ears 20 are positively held against the case to engagethe same and prevent slippage thereof.

When the cases have been transported to their destination, the truck istilted to a substantially upright position to permit the cases to reston the floor and the truck is twisted slightly with respect to thestacks causing the arms 16a and the ears carried thereby to disengagefrom the case and cause the arms 16 to be pushed to the outwardlyextending inoperative broken line position best seen in FIG. 3, thespring 21 moving forwardly past the center line and bowing forwardly topositively hold the arms 16 in open position.

FIG. 4 illustrates an alternate form of gripping assembly of myinvention which employs the same basic principles as those of thegripping assembly hereinbefore described, but varies somewhat in theactual construction and design thereof. In this alternate form, atransverse clarnp supporting bar 24 is secured to the front of the feetof the side members it as by welding and extends laterally outwardlytherefrom a short distance. A pair of vertically disposed rod-like pivotor bearing members 25 are carried on the outer ends of said supportingbar 24 and have pivotally mounted thereon and encompassed thereby a pairof clamp carrying sleeves 26. The sleeves 26 have secured thereto as bywelding the clamping arms or jaws 27 which include the forwardlyextending side portions 270 and the back portions 2711, the leading endsof the side portions 27a being provided with inwardly laterallyextending case carrying and supporting cars 28 adapted to be insertedinto the hand hold apertures '19 of the cases 17. The inner ends of theback portions 2711 have mounted thereon as by welding mounting membersor rods 29 which extend in from and beyond the outer ends of the backportions 27b, the extended portion of the mounting rods 29 being adaptedfor insertion into the ends of an elongate resilient semi-rigid deformedor bowed tensioned arm coupling and holding member 30, the mounting rods29 being provided with raised, lateral portions 31 for anchoring thearms 27 to the tensioned member 39. The inner ends of the back portions27b preferably abut with the outer ends of the tensioned member 30 toprovide a more positive action therebetween.

The tensioned member 30 operates in much the same fashion as the helicalspring 21 previously hereinbefore described and also operates on whatmight be termed an over center principle. The tensioned member 30 isadapted to bow laterally outwardly under the bending stress or tensionapplied to the ends thereof and when disposed rearwardly of the centerline between the points of pivotal connection (as defined by the bar 24)positively holds the side arm portions 27a and the cars 28 carriedthereon inwardly in a positive clamping action and when disposedforwardly of the center line positively maintains the side portions 27ain an outwardly extended open inoperative position corresponding to thebroken line position of FIG. 4. Thus, the coupling member 30 may be anelongate semi-rigid elastic element or tube of any suitable crosssectional shape and made of rubber or some other suitable materialwhich, when bent or deformed as in the accompanying drawings, resistssuch deformation or bending to such an extent that it is tensionedsufficiently to positively hold the carrying and clamping arms 27 inwhatever position desired while still being resilient enough to be ableto shift position or spring from one side of the center line to theother under the influence of the movements of back portions 27b of thecarrying arms 27.

In view of the foregoing, the advantages of my invention are readilyapparent. A beverage case truck employing the case supporting andcarrying clamp of my invention can readily pick up and disengage a stackof cases without first tilting the cases, thereby avoiding the physicalexertion, inconvenience and possible danger of tipping over the casesand breaking the contents commonly associated with tilting a stack ofcases. The tensioned coupling members whether of the coiled springvariety or the elastic bar stock type provide for substantiallynoiseless operation and further provide for smooth and efficient andpositive holding of the arms in all positions including clamping andopen inoperative position to maintain the case engaging arms either in apositive clamping engagement with the cases to be carried and supportedthereby or to positively maintain them in an outwardly extended openinoperative position. It will also be noted that the arrangementprovides for automatic shifting of the arm biasing and tensioningmembers 21 and 30 from one side of the center line to the other when thearms 16 and '27 are moved by engaging the cases or by twisting movementapplied to the truck.

It will be further appreciated that the case gripping assembly or clampof my invention is relatively inexpensive to make and mount and may bereadily adapted to almost every type of case carrying truck frame nowavailable on the market.

It will, of course, be understood that various changes may be made inthe form, details, arrangement and proportions of the various partswithout departing from the scope of my invention.

What I claim is:

l. Grasping and lifting apparatus comprising a frame, a pair ofcooperating jaw members pivotally mounted on said frame for relativeopening and closing movement therebetween for releasably holding anarticle therebetween, and spring means interconnecting said jaw membersand movable therewith between a first position when said jaws are openand a second position when said jaws are closed, said spring meansbiasing said jaws in one direction about their respective pivot axes andaway from each other and yieldingly holding said jaws open when in saidfirst position and biasing said jaws in the opposite direction abouttheir respective pivot axes and towards each other and yieldinglyholding them closed when in said second position.

2. Grasping and lifting apparatus comprising a frame, a pair of jawmembers pivotally mounted on said frame for relative opening and closingmovement therebetween about parallel axes, and spring meansinterconnecting said members and moveable therewith and adapted to shiftposition from one side to the other of a line bisecting said axes whensaid jaws move between open and closed position whereby said springmeans biases said jaw members away from each other and yieldingly holdsthem in open position when on one side of said line and biases said jawstowards one another and holds them in closed position when on the otherside of said line.

3. Grasping and lifting apparatus comprising a frame, a pair of elongatejaw members pivotally connected intermediate the ends thereof to saidframe for relative opening and closing movement therebetween, said jawmembers having opposed first end portions adapted for movement towardsand away from each other to grasp an article therebetween and second endportions offset from said first end portions and rigidly connectedthereto and extending toward each other, and spring meansinterconnecting said second end portions, said spring means beingadapted to move with said jaw members and shift position when said jawsare opened and closed whereby said first end portions are biased in onedirection relative to their respective pivot axes and away from eachother by said spring means when the jaws are open and are biased in theopposite direction relative to their respective pivot axes and towardseach other by said spring means when the jaws are closed.

4. Grasping and lifting apparatus comprising a frame, cooperating jawmembers pivotally mounted on said frame for pivotal movement aboutparallel axes, said jaw members having first end portions adapted tograsp an article therebetween and second end portions olfset from saidfirst end portions and rigidly connected thereto and extending towardsone another, a helically coiled spring member extending between andflexibly linking said second end portions together and compressivelytensioned thereby, said spring member being adapted for shiftablemovement between positions on opposite sides of a center line bisectingsaid axes of pivotal movement in response to the movements of said jawmembers in moving from inoperative to operative position, said springmember biasing said first end portions towards one another when on oneside of said center line and biasing said portions away from one anotherwhen located on the opposite side of said center line.

5. Grasping and lifting apparatus comprising a frame, cooperating jawmembers pivotally mounted on said frame for pivotal movement aboutparallel axes, said jaw members having first end portions adapted tograsp an article therebetween and second end portions offset from saidfirst end portions and rigidly connected thereto and extending towardsone another, an elongate spring member extending between and flexiblylinking said second end portions together and maintained in bowedtensioned condition thereby, said spring member being adapted forshiftable movement between positions on opposite sides of a center linebisecting said axes of pivotal movement in response to the movements ofsaid jaw members in moving from inoperative to operative position, saidspring member being bowed in one direction and biasing said first endportions towards one another when on one side of said center line andbeing bowed in the opposite direction and biasing said portions awayfrom one another when located on the opposite side of said center line.

6. Grasping and lifting apparatus comprising a frame, a pair ofcooperating jaws having elongate first end portions for grasping anarticle therebetween and elongate second end portions generally normalto said first end portions and rigidly connected thereto and extendingtowards each other, said jaws being mounted on said frame for pivotalmovement about parallel axes normal to both of said end portions, saidsecond end portions terminating in generally opposed ofiset portionsextending in a direction opposite to said first end portions, and anelongate coiled compression spring extending between said offsets andhaving its ends anchored thereto for movement therewith, said springbeing maintained in compressed tensioned state by said offsets and continuously pressing thereagainst, said spring being adapted for shiftablemovement between positions on opposite sides of a center line bisectingsaid axes of pivotal movement in response to the movements of said jawmembers in moving from inoperative to operative position, said springbiasing said first end portions towards one another when on one side ofsaid center line and biasing said portions away from one another whenlocated on the opposite side of said center line.

7 The apparatus of claim-6, wherein said offset portions are bent backupon said second end portion and define therewith an angle less thanReferences Cited in the file of this patent UNITED STATES PATENTS2,292,234 Malo Aug. 4, 1942 2,651,427 Butler Sept. 8, 1953 2,720,992Cushman Oct. 18, 1955 2,954,886 Nelson Oct. 4, 1960 FOREIGN PATENTS76,928 Netherlands Jan. 15, 1955

1. GRASPING AND LIFTING APPARATUS COMPRISING A FRAME, A PAIR OFCOOPERATING JAW MEMBERS PIVOTALLY MOUNTED ON SAID FRAME FOR RELATIVEOPENING AND CLOSING MOVEMENT THEREBETWEEN FOR RELEASABLY HOLDING ANARTICLE THEREBETWEEN, AND SPRING MEANS INTERCONNECTING SAID JAW MEMBERSAND MOVABLE THEREWITH BETWEEN A FIRST POSITION WHEN SAID JAWS ARE OPENAND A SECOND POSITION WHEN SAID JAWS ARE CLOSED, SAID SPRING MEANSBIASING SAID JAWS IN ONE DIRECTION ABOUT THEIR RESPECTIVE PIVOT AXES ANDAWAY FROM EACH OTHER AND YIELDINGLY HOLDING SAID JAWS OPEN WHEN IN SAIDFIRST POSITION AND BIASING SAID JAWS IN THE OPPOSITE